Filter



Nav.- 30, 1937. R. l.. IRWINE 2,100,482

FILTER 3 I Filed June 24, 1936 2 sheets-sheet .-y

INVENTQR www ATTORNEY,

Patented Nov. a0, 1937 UNITED STATES FILTER Robert L. Irwine, Union, N. J., assigner to Motor j Improvements, Inc., Newark, N. J., a corporation of Delaware Application June 24, 1936, Serlal No: 86,943

11 Claims.

This invention relates to lters and more especially to a filter for removing solid particles from a liquid used as the cooling medium for grinding wheels, cutting tools and the like. In ordinary factory practice, suchcooling medium' is circulated through a system comprising a tank and suitable conduits for supplying the cooling medium from the tank to the tool and returning the cooling medium from the tool to the tank. The 1o cooling medium becomes contaminated with solid particles cut by the tool from the work upon which it is operating and the presence of such solid particles in the cooling medium is highly undesirable for certain types of manufacturing operations.

An object of this invention is a self-cleaning filter, particularly adapted to remove solid particles from the cooling medium used with certain types of cutting machines which will operate eiliciently-without attention for long periods.

In a lfilter embodying the invention, a tubular ltering element, preferably of the metal ribbon type disclosed in the patent to Liddell, No. 2,042,- 537 is caused to rotate in the cooling medium tank and cooling medium is sucked in through the interstices of the element, solid particles being removed from the cooling medium and being collected on the outer surface of the filtering element. The major portionof the iiltered cooling medium is delivered to the tool to be cooled, but a portion of the cooling medium is caused to ow reversely through the rotating ltering elementv in a thin stream extending from one end of the element to the other. Thus, a layer or coat of ltrate is prevented from forming on the outer outer surface of the lter element. Preferably,

the cooling medium is sucked in through the iilter element and delivered to the tool by an impeller located within the filtering element and the stream of filtered cooling medium is -used to effect rotation of the filter element. Other objects, novel features and advantages of this invention will become apparent from the following description and accompanying drawings, wheren:

Fig. 1 is a side elevation of a filter embodying the invention assembled with a tank, the latter being shown in vertical section;

Fig. 2 is a vertical section through a iilter embodying the invention;

Fig. 3 is a section on the line 3-3 oi Fig. 2; Fig. 4 is a section on the line 4-4 of Fig. 2;

Fig. 5is a section on the line 5 5 of Fig. 2, and

Fig. 6 is a perspective fview of the impeller.

Any suitable tank I0 may be used to contain a supply of cooling medium and is provided with iianges, cross-bars or the like on which is mount- 5 ed a cored head II, the head being attached to the tank by bolts I2 or other suitable means. A motor I3 is mounted on the upper end of the head I I in any suitable manner.

A tubular housing I4 has its upper end threaded into the lower end of a passageway I5 formed'in the head I I and in the other end of the passageway I5 is threaded one end of a pipe I 6.' The lower end of the housing I4 is of greater diameter than the upper end and in it isrotatably arranged 15 a sleeve I'I. A second sleeve I8 surrounds the upper end of the housing I4 and is journalled in the head I I by a suitable ball-bearing I9 which is assembled with the head II by means of a bushing 20 provided with attaching bolts 2l. A collar 22 is attached to the lower end of the sleeve I8 by screws 23.

A ring 24 is attached to the collar 22 by bolts 25 passing through ears 24a on the ring 24 and the flange portion of the collar. A cylindrical 25 frame 26 is attached at its upper end tothe ring 24 by screws 21 and is attached at its lower end to a cap 28 by screws 29. The frame 26 is provided with a large number of elongated apertures over its major portion and is enclosed by a cylin- 30 drical illtering element 30. The illtering element 30 comprises a-helix of metal ribbon having contactingl turns and being provided with spacing means to provide filtering, interstices, such ltering element being fully disclosed and claimed in the aforementioned patent to Liddell, No. 2,042,537. The ends of the iiltering element are received in grooves formed by the ends of the frame 2li-with the ring 24 and cap 28.

The cap 28 is provided with a boss 3i equipped -40 with cross grooves in which are received the bottom edges of a cross-shaped metal member 32, the uppery edges of which t in cross cuts in the bottom edge of the sleeve I'I. A shaft 33 is attached at its upper end by a screw 34 to a head 45 35 which is journalled in the head II by a ballbearing 36.' The lower end of the shaft 33 is journailed in a bearing 31 provided near the lower end of the housing, this bearing being supported by arms 31a projecting inwardly from the inner 50 periphery of the casing. A three-blade impeller y 38 vis attached to the lower end of the shaft I2. A hub 39 is rotatably mounted on the shaft 22 I between the impeller 38 and the bearing 31. The hub 39 has top and bottom conical faces, the 55 1 of the ltering element. 30.

angularity of the top face being greater than that of the bottom face. Blades 40 are mounted in slots cut in the hub in angular relation to radii and impinge the' inner periphery of the sleeve I1 so that the latter rotates with the hub 39. A tube 4I is attached to the outer periphery of the housing I4 and is of substantially the same length as the filter element 30. The tube 4I is slotted along aline parallel tothe axis of the filtering element and is so arrangedl as to discharge liquid 4from the tube'into contact with the inner periphery of the ltering element 30 along a. line extending from one end to the other of the illtering element. 'I'he tube 4I is in connection with the interior of the housing I4 through the medium of a passageway 43 extending through the wall ofthe housing and the wall of the tube.

In the operation of the apparatus Just described, the motor I3 which is suitably connected to the upper end of the shaft 33 rotates the impeller 38 at a relatively high speed. The impeller sucks liquid through the interstices of the filter element 30 into the bottom of the housing and drives such liquid under pressure through the passageway I5 into the pipe I6 and through the same to the tool to be cooled. The stream of filtered liquid ows through the passageways formed in the sleeve I1 by the vanes 40, causing rotation thereof at a much slower rate than the rotation of the impeller 38. The cap 23 is caused to rotate with the sleeve I1 through the medium of the cross-shaped member 32` with the consequentrotationof the entire illterlng element and its supporting structure. A portion cf the filtered liquid is directed through the passageway 43 into the tube 4I from which it is discharged through the slot 42 against the inner periphery The force of the stream discharged through the slot 42 is suilicient to cause reverse iiow through the filtering element thereby dislodging any filtrate that may have been deposited thereon. Rotation of the filtering element causes such action to be spread over the entire surface of the ltering element with the result that it is continuously maintained clean. Liquid from the tool is returned to the tank III through the pipe lila. Vertical fins 44 are provided for preventing swirling of the liquid within the filtering element, the tube 4I also serving in the same respect.

The impeller 38 consists of a hub 38a having three spiral grooves. In each of these grooves is arranged an arcuate plate 33h.' the plates being so oriented with respect to each other that their leading edges are approximately apart and lie in the same plane perpendicular to the axis of rotation. The trailing edges are arranged inthe same space relation land are pro. vided with up-turned edges 38e.

I claim:

l. A self-cleaning lter comprising a tubular rotatable filtering element, rotary pump means within said nltering element and having its inlet communicating with the interior of said ltering element, a discharge passage for filtered liquid, a distributor for directing a thin stream of liquid against the inner surface of said filtering ele.

ment from one end to the other thereof, said pump means having its outlet -communicating both with said discharge passage and said disjtributor, means for driving said pump means for sucking liquidA through said filtering element and lsupplying a portion thereofunder pressure to said distributor, and means associated with said Pump for rotating said ltering element.

inner surface of said -nltering element.

l ,2.-A self-cleaning iilter according to claim 1 in which the distributor comprises a tube within said filtering element extending parallel to the axis thereof and being apertured along a line parallel to the .tube axis.

3. A self-cleaning lter comprising a tubular rotatable ltering element, a stationary housing within said illtering element, a tube carried by said housing and being apertured along a line extween said rotary element and filter elemen'tfor' eiecting rotation of the latter by the former.

4. A self-cleaning lter comprising a stationary tubular housing, a rotatable tubular filter element enclosing said housing, a shaft journalled in a rotatable element journalled in said housing in along a line parallel to its `own axis, said impeller being effective upon rotation to suck liquid through said filter element and discharge it through said rotatable member, a portion of `the fluid being passed into said tube and projected in a thin stream against the-interiorsurface-of said lter element. y y

5. A nlter comprising a head. a cylindrical illtering element rotatably supported thereby, a tubular housing carried by said head and extending into said filtering element, said head having a passageway communicating with said housing, pump means in said housing lfor sucking liquid through said filtering element and discharging the same through said housing into said passageway, a rotatable member in said housing operable by liquid discharged from said pump means, and means connecting said rotarymember and filtering element for effecting rotation of the latter by the former.

6. A lter according to claim 5 wherein means are provided for projecting liquid against the inner surface of said filtering element, said means being in communication with said housing.

7. A nlter comprising a head, a cylindrical illtering element rotatably supported thereby, a tubular casing carried by said head and extending into said filtering element, said head having a passageway communicating with said housing, a shaft journalled in said housing, an impeller fixed to said shaft and eifective upon rotation to suck liquid through said filtering element and ,discharge the same through said housing into' said passageway, a sleeve rotatable in said housing and having passageways through which liquidl 'is discharged from said impeller to eiIect rotation and ltering element for effecting rotation of the latter by the former.

8. A filter according to claim "I in which a tube communicating with the interior of said housing is supported by said housing, said tube Abeing apertured to project liquid therefrom against the 9. A filter comprising a head, acylindrical ltering element rotatably supported thereby. a tubular housing carried by said head and extending'into said filtering element,- said head having a passageway communicating with said housing,

zo said housing, an impeller mounted on said shaft,

a shaft journalled in said housing. an impeller xed to said shaft and eiective upon rotation to suck in liquid through said iltering element and discharge the same through said housing into said passageway, a rotatable element in said housing operable by liquid discharged by said impeller, and connections between said rotatable element and ltering element for effecting rotation'of the latter by the former.

10. A lter according to claim 9 wherein means are provided for diverting liquid from said housing into contact with the inner surface of said ltering element.

11. A self-cleaning lter comprisinga tubular i 3 rotating filtering element, pump means within said illtering element and havingits inlet communicating with the interior of said filtering element, means for operating said pump means to suck liquid through said filtering element, a passage into which said pump discharges, means within said filtering element and operable by liquid discharged from said pump means for effecting rotation of said ltering element. and means for diverting a portion o! the liquid discharged froni said pump into contact with' the inner surface of said filteringelement.

ROBERT L. 

